我有一张 table
ABC (id, type_id, x, y, z)
这 5 个表:
x(id, title, address_id, my-X-Related-Values)
y(id, title, address_id, my-Y-Related-Values)
z(id, title, address_id, my-Z-Related-Values)
address(id,address)
type(id,title)
ABC中的x,y,z分别指的是x.id,y.id,z.id。
注意,ABC 的每一行中只有 x 或 y 或 z 具有值,其他均为 NULL。
输入表格:
id:1 ---- title:'hello x'
id:2 ---- title:'你好'
id:3 ---- title:'hello z'
到目前为止我已经完成了此操作,但不知道如何继续处理 y 和 z 表:
SELECT ABC.id ,type.title AS type,address.address FROM ABC
INNER JOIN address,type,x,y,z
WHERE ABC.x = x.id AND
address.id = x.address_id
编辑: 我有这六个查询,我只想在一个查询中执行:
$string = "SELECT melk_standardize.melk_id ,bongah.title AS bongah,deal_type.title AS deal,apartment.address AS address,melk_types.title AS type FROM melk_standardize
INNER JOIN bongah,apartment,deal_type,melk_types WHERE melk_standardize.apartment_id = apartment.apartment_id AND bongah.id = apartment.bongah_id AND deal_type.id = apartment.deal_type AND melk_types.id = 1 ORDER BY apartment.apartment_id";
$string = "SELECT melk_standardize.melk_id ,bongah.title AS bongah,deal_type.title AS deal,apartment_presale.address AS address,melk_types.title AS type FROM melk_standardize
INNER JOIN bongah,apartment_presale,deal_type,melk_types WHERE melk_standardize.apartment_presale_id = apartment_presale.apartment_presale_id AND bongah.id = apartment_presale.bongah_id AND deal_type.id = apartment_presale.deal_type AND melk_types.id = 2 ORDER BY apartment_presale.apartment_presale_id";
$string = "SELECT melk_standardize.melk_id ,bongah.title AS bongah,deal_type.title AS deal,house.address AS address,melk_types.title AS type FROM melk_standardize
INNER JOIN bongah,house,deal_type,melk_types WHERE melk_standardize.house_id = house.house_id AND bongah.id = house.bongah_id AND deal_type.id = house.deal_type AND melk_types.id = 3 ORDER BY house.house_id";
$string = "SELECT melk_standardize.melk_id ,bongah.title AS bongah,deal_type.title AS deal,garden.address AS address,melk_types.title AS type FROM melk_standardize
INNER JOIN bongah,garden,deal_type,melk_types WHERE melk_standardize.garden_id = garden.garden_id AND bongah.id = garden.bongah_id AND deal_type.id = garden.deal_type AND melk_types.id = 4 ORDER BY garden.garden_id";
$string = "SELECT melk_standardize.melk_id ,bongah.title AS bongah,deal_type.title AS deal,shop.address AS address,melk_types.title AS type FROM melk_standardize
INNER JOIN bongah,shop,deal_type,melk_types WHERE melk_standardize.shop_id = shop.shop_id AND bongah.id = shop.bongah_id AND deal_type.id = shop.deal_type AND melk_types.id = 5 ORDER BY shop.shop_id";
$string = "SELECT melk_standardize.melk_id ,bongah.title AS bongah,deal_type.title AS deal,ground.address AS address,melk_types.title AS type FROM melk_standardize
INNER JOIN bongah,ground,deal_type,melk_types WHERE melk_standardize.ground_id = ground.ground_id AND bongah.id = ground.bongah_id AND deal_type.id = ground.deal_type AND melk_types.id = 6 ORDER BY ground.ground_id";
最佳答案
为每个表添加单独的联接并指定每个联接的条件。我假设您想要在 x、y 和 z 上加入 ABC,其中 ABC 是任何 x、y 或 z 匹配项。
不确定这是否能给你真正想要的东西,但我认为它已经很接近了。
SELECT ABC.id AS id, type.title AS type, address.address AS address
FROM ABC
JOIN address ON (ABC.id = address.id)
JOIN type ON (ABC.id = type.id)
JOIN x ON (ABC.x is NULL OR ABC.x = x.id)
JOIN y ON (ABC.y is NULL OR ABC.y = y.id)
JOIN z ON (ABC.z is NULL OR ABC.z = z.id)
关于mysql - 根据条件从不同的表中选择,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/33903138/